Multi-zonal monofocal intraocular lens for correcting optical aberrations

Abstract

A multi-zonal monofocal opthalmic lens comprises an inner zone, an intermediate zone, and an outer zone. The inner zone has a first optical power. The intermediate zone surrounds the inner zone and has a second optical power that is different from the first power by a magnitude that is less than at least about 0.75 Diopter. The outer zone surrounds the intermediate zone and has a third optical power different from the second optical power. In certain embodiments, the third optical power is equal to the first optical power.

Description

RELATED APPLICATION[0001]The present application claims priority under 35 U.S.C §119(e) to provisional application No. 60 / 424,851, filed on Nov. 8, 2002 under the same title. Full Paris Convention priority is hereby expressly reserved.FIELD OF THE INVENTION[0002]This invention relates to intraocular lenses (IOLs) and, more particularly, to multi-zonal monofocal IOLs that correct optical aberrations for a variety of human eyes with different corneas under a wide range of lighting conditions and that are effective even when decentered or tilted.BACKGROUND OF THE INVENTION[0003]In the perfect eye, an incoming beam of light is focused through the cornea and through the crystalline lens in a way that causes all of the light from a point source to converge at the same spot on the retina of the eye, ideally on the fovea area of the retina. This convergence occurs because all of the optical path lengths, for all light in the beam, are equal to each other. Stated differently, in the perfect ...

AI Technical Summary

Benefits of technology

[0015]The present invention provides a multi-zonal monofocal ophthalmic lens that is less sensitive to its disposition in the eye by reducing aberrations, including the spherical aberration, over a range of decentration. The monofocal ophthalmic lenses of the present invention may also be configured to perform well across eyes with different corneal aberrations (e.g., different asphericities).

Problems solved by technology

Not all eyes, however, are perfect.

The consequences of this are that light path lengths through the eye become distorted and are not all equal to each other.

As one grows older, the spherical aberration of the crystalline lens becomes more positive, increasing the overall spherical aberration and reducing the image quality at the retina.

In real eyes with complex corneal aberrations, the eye following cataract surgery is left a with finite number of complex lower and higher order aberrations, limiting the image quality on the retina.

Slight errors in decentration (radial translation) or tilt (axial rotation) greatly reduces the effectiveness of the lens, especially in low-light conditions, thus making the task of the surgeon more difficult.

Furthermore, shrinkage of the capsular bag or other post-implantation anatomical changes can affect the alignment or tilt of the lens along the eye's optical axis.

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